The present invention relates to a packing machine.
In particular, the present invention relates to a packing machine for forming semi-finished packets of cigarettes.
Known cigarette packing machines normally comprise a wrapping conveyor for producing a succession of wrappings, each containing a respective group of cigarettes; an overwrapping conveyor for receiving the wrappings from the wrapping conveyor at a transfer station, and folding a respective blank partially about each wrapping to form a semi-finished packet of cigarettes; and an output conveyor for orienting the semi-finished packets and finish-folding the blanks about the respective wrappings.
More specifically, the wrapping conveyor and the overwrapping conveyor are arranged in series along a straight input portion of a packing path, and comprise respective conveying branches located side by side at said transfer station, and respective numbers of conveying pockets for respectively feeding the wrappings and the packets crosswise to the long longitudinal axes of the wrappings and packets, and which are engaged longitudinally by an unloading device at the transfer station to transfer each wrapping from one pocket to another.
The output conveyor of packing machines of the above type is normally defined by a carousel conveyor comprising a number of conveying heads for removing the packets off the overwrapping conveyor, orienting the packets, and feeding them along a straight output portion of the path crosswise to said input portion.
Known packing machines of the above type involve numerous technical, functional and structural drawbacks on account of the series arrangement of the conveyors along the packing path, which results in an extremely bulky machine and, consequently, in in-plant layout problems during installation. Moreover, in most cases, the packets are transferred between the conveyors and between the overwrapping conveyor and unloading device with no provision for firmly and accurately retaining the wrappings or packets, i.e. with no provision for preventing the wrappings or packets, which are not yet stabilized, from tearing. Finally, employing an unloading device of the type described, or for that matter any known unloading device, prevents not only the formation of a completely straight packing path, but also the attainment of high output speeds.